[Solved] Openhab 2.4 Homematic binding

Is there something else changed with homematic binding 2.4 beside moving it to eclipse namespace?
I’m using Homematic CCU2 firmware 2.41.5 (latest). When I update from working 2.3 system to openhab 2.4 the Homematic items are not working any more. The brigde and the other homematic things are shown as Online in Paper UI. But Homematic actors are not working. All my other 2.4 bindings are working well.

I’m tired of analyzing debug log’s. My system is in “production” mode.
I downgraded to openhab 2.3 and everyting is fine.
If someone knows something about it, please let me know.

I installed a new clean openHAB 2.4 test system with homematic binding only.
I do not use the automatic recognized things from Paper UI InBox, I prefere to use my own configuration files.
I created a simple sitemap, thing and item file with homematic bridge, one homematic thing and one linked item.
It’s working as expected.
So there is no common problem with homematic binding in openHAB 2.4.

But I cannot understand why it’s not working after updating the running system to 2.4 and it is running again after downgrading to 2.3.

So what, never change a running system. Maybe I try it again later…

Did you clean the chache?

Yes, cache was cleaned.
The first attempt was without cleaning cache, I’ve got a 2.4 runtime with 2.3 bindings.
I purged the installation, installed 2.4 again, restored my 2.3 backup, cleaned the cache, then started the service.

Finally I solved the problem.
I’m using the MySQL persistence binding. With openHAB 2.4 I’ve got a DB connection error:

2019-05-04 14:15:06.405 [ERROR] [sql.internal.MysqlPersistenceService] - mySQL: Failed connecting to the SQL database 
using: driverClass=com.mysql.jdbc.Driver, url=jdbc:mysql://, user=openhab
java.sql.SQLException: The server time zone value 'CEST' is unrecognized or 
represents more than one time zone. 
You must configure either the server or JDBC driver
(via the serverTimezone configuration property) to use a more specifc time zone value 
if you want to utilize time zone support.

Running this at my SQL server solved the DB connection problem:

SET @@global.time_zone = ‘+00:00’;
SET @@session.time_zone = ‘+00:00’;

Now all bindings are running with openHAB2.4